{"id":"F2006B04612","name":"AD/BELL 222/21 - Vertical Fin Attachment Bolt","slug":"ad-bell-222-21-vertical-fin-attachment-bolt","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44364,"registerId":"commonwealth-F2006B04612-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BELL 222/21 - Vertical Fin Attachment Bolt","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nBell Helicopter Textron Canada (BHTC) 222 Series Helicopters\n\nAD/BELL 222/21 Vertical Fin Attachment Bolt 12/98\n\nDM\n\nApplicability: All Bell Helicopter Textron Canada (BHTC) Model 222, 222B, and 222U helicopters. Requirement: 1. Check the torque on the vertical fin attachment bolts as outlined in Part I of Alert\n\nService Bulletin (ASB) 222-98-82 Revision A or 222U-98-53 Revision A, as\n\napplicable.\n\n    2. Inspect and reattach the fin as outlined in Part II of the ASBs noted in Requirement 1, as applicable.\n\n    3. Verify the correct torque of the attachment bolts as outlined in Part III, Special Inspections, of the ASBs noted in Requirement 1, as applicable.\n\nNote: Transport Canada AD CF-98-21 refers.\n\nCompliance: 1. Unless already accomplished, within 25 hours time in service after 16 September 1998.\n\n    2. At or before the next scheduled 150-hour inspection, but not later than 31 December 1998.\n\n    3. Within 5 to 10 hours time in service after compliance with the Requirement 2 inspection.\n\nThis Airworthiness Directive becomes effective on 16 September 1998.\n\nBackground: BHTC received a report of a loss of torque of the vertical fin attachment bolts on a Model 230 helicopter. This condition resulted in a loose fin with four of the eight attachment bolts being fractured. The Model 230 helicopter is of similar design to the Model 222 series.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This Airworthiness Directive maintains its original narrow scope. It addresses a specific safety-of-flight issue (vertical fin attachment bolt integrity) identified through a reported incident on a related aircraft model. The requirements remain tightly focused on the inspection and re-torquing of specific hardware on specific helicopter models, with no expansion into unrelated systems or operational matters."},"complexity_factors":["Single, specific mechanical issue addressed (vertical fin bolts)","Only 3 sequential requirements with clear cross-references to manufacturer bulletins","Straightforward compliance timeline with two alternative deadlines (hours-based or calendar-based)","No nested exceptions or conditional logic — requirements apply to all listed models uniformly","Minimal defined terms (only standard aviation terminology like 'time in service')","Short document (approximately 200 words) with single-purpose scope"],"plain_english_summary":"This mandatory safety order requires owners/operators and maintenance crews of Bell 222, 222B, and 222U helicopters to perform targeted checks and reattachment procedures on the bolts securing the vertical tail fin to prevent detachment. It was issued after a Bell 230 suffered multiple broken bolts and a loose fin; complying is legally required because fin failure can cause loss of control and a crash."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive applies to the specified Bell 222 series models and responds to a reported bolt failure on a similar design. The source text shows no indication the instrument’s scope was altered from that stated intent."},"complexity_factors":["References external manufacturer Alert Service Bulletins for the required inspection and reattachment procedures (Requirement 1–3).","Multiple, short compliance deadlines create scheduling pressure (Compliance: 25 hours after 16 Sep 1998; by next 150‑hour inspection but not later than 31 Dec 1998; 5–10 hours after Requirement 2).","Technical maintenance tasks (torque checks, inspection, reattachment, special inspections) require qualified personnel and workshop time (Requirement 1–3).","Applicability to all BHTC Model 222, 222B and 222U helicopters broadens operational impact (Applicability).","Cross-reference to Transport Canada AD CF‑98‑21 adds regulatory interdependence (Note).","Background report of fractured bolts on a similar Model 230 implies potential for part replacement and operational downtime (Background)."],"plain_english_summary":"Requires operators of Bell 222, 222B and 222U helicopters to inspect, verify torque, and if needed reattach the vertical fin attachment bolts following the manufacturer’s Alert Service Bulletin. Owners/operators bear the inspection and repair costs and must comply within short, specified timeframes set by the Civil Aviation Safety Authority. The directive follows a report of bolt loosening and fractured fasteners on a similar-model helicopter."},"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"}},"importantCases":[],"_links":{"self":"/api/acts/ad-bell-222-21-vertical-fin-attachment-bolt","history":"/api/acts/ad-bell-222-21-vertical-fin-attachment-bolt/history","analysis":"/api/acts/ad-bell-222-21-vertical-fin-attachment-bolt/analysis","conflicts":"/api/acts/ad-bell-222-21-vertical-fin-attachment-bolt/conflicts","importantCases":"/api/acts/ad-bell-222-21-vertical-fin-attachment-bolt/important-cases","documents":"/api/acts/ad-bell-222-21-vertical-fin-attachment-bolt/documents"}}